package Tree;

public class _617_MergeTwoBinaryTrees {
    public TreeNode mergeTrees(TreeNode t1, TreeNode t2) {
        if(t1==null || t2==null) return t1 == null ? t2 : t1;
        t1.val = t1.val + t2.val;
        t1.left = mergeTrees(t1.left, t2.left);
        t1.right = mergeTrees(t1.right, t2.right);
        return t1;
    }
}
